from datetime import datetime
from os import abort
from flask import render_template, flash, redirect, url_for, request, current_app,jsonify
from flask_login import current_user, login_required
from app.ext import db
from app.main.forms import EditProfileForm, PostForm,EmptyForm
from app.models import User, Post
from app.main import main_bp
from app.main.forms import EditPostForm
from app.main.forms import MessageForm
from app.models import Message
from app.models import Notification

@main_bp.before_app_request
def before_request():
    if current_user.is_authenticated:
        current_user.last_seen = datetime.utcnow()
        db.session.commit()


@main_bp.route('/')
@main_bp.route('/index', methods=['GET', 'POST'])
@login_required
def index():
    form = PostForm()
    if form.validate_on_submit():
        post = Post(body=form.post.data, author=current_user)
        db.session.add(post)
        db.session.commit()
        flash('你的帖子已发表!')
        return redirect(url_for('main.index'))
    page = request.args.get('page', 1, type=int)
    posts = current_user.followed_posts().paginate(page, current_app.config['POSTS_PER_PAGE'], False)
    next_url = url_for('main.index', page=posts.next_num) \
        if posts.has_next else None
    prev_url = url_for('main.index', page=posts.prev_num) \
        if posts.has_prev else None
    return render_template('index.html', title='首页', form=form,
                           posts=posts.items, next_url=next_url,
                           prev_url=prev_url)



@main_bp.route('/user/<username>')
@login_required
def user(username):
    user = User.query.filter_by(username=username).first_or_404()
    page = request.args.get('page', 1, type=int)
    posts = user.posts.order_by(Post.timestamp.desc()).paginate(page, current_app.config['POSTS_PER_PAGE'], False)
    next_url = url_for('main.user', username=user.username, page=posts.next_num) \
        if posts.has_next else None
    prev_url = url_for('main.user', username=user.username, page=posts.prev_num) \
        if posts.has_prev else None
    return render_template('user.html', user=user, posts=posts.items,
                           next_url=next_url, prev_url=prev_url)



@main_bp.route('/edit_profile', methods=['GET', 'POST'])
@login_required
def edit_profile():
    form = EditProfileForm(current_user.username)
    if form.validate_on_submit():
        current_user.username = form.username.data
        current_user.about_me = form.about_me.data
        db.session.commit()
        flash('你的信息已提交')
        return redirect(url_for('main.user',username=current_user.username))
    elif request.method == 'GET':
        form.username.data = current_user.username
        form.about_me.data = current_user.about_me
    return render_template('edit_profile.html', title='Edit Profile',
                           form=form)


@main_bp.route('/follow/<username>',methods=['GET', 'POST'])
@login_required
def follow(username):
    user = User.query.filter_by(username=username).first()
    if user is None:
        flash('用户:{} 未找到'.format(username))
        return redirect(url_for('index'))
    if user == current_user:
        flash('你不能关注自己！')
        return redirect(url_for('main.user', username=username))
    current_user.follow(user)
    db.session.commit()
    flash('已经关注用户: {}!'.format(username))
    return redirect(url_for('main.user', username=username))

   
@main_bp.route('/unfollow/<username>',methods=['GET', 'POST'])
@login_required
def unfollow(username):
    user = User.query.filter_by(username=username).first()
    if user is None:
        flash('用户:{} 未找到'.format(username))
        return redirect(url_for('main.index'))
    if user == current_user:
        flash('你不能取消关注自己！')
        return redirect(url_for('main.user', username=username))
    current_user.unfollow(user)
    db.session.commit()
    flash('已经取消关注用户: {}.'.format(username))
    return redirect(url_for('main.user', username=username))


@main_bp.route('/explore')
@login_required
def explore():
    page = request.args.get('page', 1, type=int)
    posts = Post.query.order_by(Post.timestamp.desc()).paginate(page, current_app.config['POSTS_PER_PAGE'], False)
    next_url = url_for('main.explore', page=posts.next_num) \
        if posts.has_next else None
    prev_url = url_for('main.explore', page=posts.prev_num) \
        if posts.has_prev else None
    return render_template("index.html", title='导航', posts=posts.items,
                          next_url=next_url, prev_url=prev_url)
    

@main_bp.route('/post/<int:id>')
def post(id):
    post = Post.query.get_or_404(id)
    return render_template('post.html',posts = [post])


@main_bp.route('/edit_post/<int:id>', methods = ['GET','POST'])
@login_required
def edit_post(id):
    post = Post.query.get_or_404(id)
    if current_user.id != post.user_id :
        abort(403)
    form = EditPostForm()
    if form.validate_on_submit():
        post.body = form.body.data
        post.timestamp = datetime.utcnow()
        db.session.add(post)
        db.session.commit()
        flash('文章已更新')
        return redirect(url_for('main.post',id = post.id))
    elif request.method == 'GET':
        form.body.data = post.body
        return render_template('edit_post.html', form=form)
    

@main_bp.route('/user/<username>/popup')
@login_required
def user_popup(username):
    user = User.query.filter_by(username=username).first_or_404()
    form = EmptyForm()
    return render_template('user_popup.html', user=user, form=form)


@main_bp.route('/send_message/<recipient>', methods=['GET', 'POST'])
@login_required
def send_message(recipient):
    user = User.query.filter_by(username=recipient).first_or_404()
    form = MessageForm()
    if form.validate_on_submit():
        msg = Message(author=current_user, recipient=user,
                      body=form.message.data)
        db.session.add(msg)
        db.session.commit()
        user.add_notification('unread_message_count', user.new_messages())
        db.session.commit()
        flash('你的消息已发送')
        return redirect(url_for('main.user', username=recipient))
    return render_template('send_message.html', title='发送消息',form=form, recipient=recipient)


@main_bp.route('/messages')
@login_required
def messages():
    #使用当前时间更新User.last_message_read_time
    current_user.last_message_read_time = datetime.utcnow()
    current_user.add_notification('unread_message_count', 0)
    db.session.commit()
    page = request.args.get('page', 1, type=int)
    messages = current_user.messages_received.order_by(
                                                    Message.timestamp.desc()).paginate(
                                                            page, current_app.config['POSTS_PER_PAGE'], False)
    next_url = url_for('main.messages', page=messages.next_num) \
        if messages.has_next else None
    prev_url = url_for('main.messages', page=messages.prev_num) \
        if messages.has_prev else None
    return render_template('messages.html', messages=messages.items,
                           next_url=next_url, prev_url=prev_url)
    
    
@main_bp.route('/notifications')
@login_required
def notifications():
    since = request.args.get('since', 0.0, type=float)
    notifications = current_user.notifications.filter(
        Notification.timestamp > since).order_by(Notification.timestamp.asc())
    return jsonify([{
                    'name': n.name,
                    'data': n.get_data(),
                    'timestamp': n.timestamp
                    } for n in notifications])


